I am currently coding in Solidity and although I have tried porting the solution over to Solidity, Solidity does not support multi-type arrays to my knowledge which is required by the rlp_encoder function. Any help or tips on how to achieve this in Solidity would be appreciated! (The nonce would be given as input during the contract creation)

Haven't tried this but you shouldn't need nested arrays or anything since all you are encoding is 2 items of known length github.com/ethereum/wiki/wiki/RLP - something like 0x08 + address length + address as bytes +0x08 + nonce length + nonce as bytes?
– Edmund EdgarAug 13 '17 at 4:22

I am also intrigued as to why you want to do this?
– Thomas ClowesAug 13 '17 at 11:22

@EdmundEdgar Would you kindly post an example of how you would proceed with doing the addition you are referring to? Should overflow checking be done or is the addition bitwise or something? Thanks in advance.
– Alex PapageorgiouAug 14 '17 at 2:40